Socket for incandescent electric lamps



P E. R'LKNOWLESL SOCKET FOR INGANDBSGENT ELECTRIC LAMPS. No. 516,820. 1v Patented'Mar. 20,; 1894.

UNITED STAT S EDWARD R. KNOWLES, OF MIDDLETOWN, CONNECTICUT, ASSIGNOR TO THE PATENT QFFICEQ SCHUYLER ELECTRIC COMPANY, OF CONNECTICUT.

SOCKET FOR INCANDESCTENT ELECTRIC LAMPS.

SPECIFICATION forming part of Iletters Patent No. 516,820, dated March 20, 1894. I Application filed December 9, 1892. Serial No. 454,663. (No model.) I

To all whom it may concert Be it known that I, EDWARD R. KNowLEs, a

citizen of the United States, residing at Midand its object is to simplify the construction,

and increase the efficiency, of the socket switches used to open and close the circuit of an incandescent electric lamp.

The invention consists in a snap switch of compact form adapted to be inclosed in the lamp socket.

In the drawings,-Figure 1 is an enlarged elevation of a lamp socketpartly broken away to show the switch. Fig. 2 is a plan view, with the base removed. Fig. 3 is an elevation of one side of the switch. Fig. 4 is an elevation of the other side; and Fig. 5 is a detail.

The base A of thesocket, and its attached shell B, may be of any suitable pattern, the shell being indented at two places on each side to form parallel guides b, 6,. into which slides the block C, of hard rubber or other insulating material. The block is preferably rectangular, as shown, and has on one side a neck 0 to receive and afford a bearing for the turning handle D, which has a reduced stem (:1 extending through the block-and projecting beyond the other side thereof. A cavity is formed in this side of the block, preferably circular, and concentric with the stem d, and into the cavity is fitted a thick washer E of hard insulating material, such as compressed fiber.

vided with one or more teeth 6, to interlock with suitable grooves in the end of the cavity and keep the washer from rotating. The'same result may be accomplished .by making the cavity and the washer polygonal. The outer face of the washer is formed into four ratchet The inner face of the washer is pro Secured to one side of the block C by a screw f is a metallic plate F, which has a fin:

ger f, overlapping and conforming to the inclined surface of one of the ratchet teeth e. The other end of the plate extends'under the block, being properly shaped to make contact with one of the lamp terminals. I have shown it as bent into a semi-circle. The inclined surface of the opposite ratchet tooth is similarly covered bya finger g projecting from a plate G secured to the block by a screw 9. On the other side of the block is a plate H, secured by a screw h, the lower end of the plate projecting under the block, in position to make contact with the other lamp terminal. The block may be notched at c, if desired, to give free play to this end of the plate. It is'understood, of course, that when the lamp is inserted into the socket, the lamp terminals come in contact with these free ends of the plates F, H, which, being resiliout, exert a yielding pressure against the conis preferred to slot the stem lengthwise, and to insert the cross-bar in the slot. The slot- ..ted portion of the stem is tubular to receive ahelical spring L, which abuts against a pin M at the outer end of the stem, and against the bar'K at its other end. The pin is thus free to move axially along the stem, and is compelled to rotate therewith, being prevented from slipping out by the walls of the cavity in which the washer E is seated. When the stem is turned, the bar rides up the inclined against the ratchet teeth 6' by a spring. It

surfaces of two opposite teeth of the ratchet, 5

and snaps down over the abrupt shoulders upon the other two inclines. In the position in which it is shown in Fig. 4, the bar connects the fingers f g, and the circuit is closed through the lamp. Upon giving the handle IOO a quarter turn, the bar snaps ofi the ends of the fingers upon the exposed teeth e of the insulating washer, and the circuit is broken.

Having thus described my invention, what I claim is- 1. A switch for an incandescent electric lamp, comprising a block of insulating material having a cavity, a washer of hard insulating material seated in said cavity, and provided with ratchet teeth on its outer face, a rotatable stem projecting through said washer and carrying a yielding crossbar, and contact plates having fingers overlapping two of said ratchet teeth, substantially as described.

2. An incandescent lamp switch, comprising a block of insulating material,arotatable stem passing through said block, an axially yielding cross-bar carried by said stem, a washer of insulating material surrounding said stem and interlocking with said block, and alternate conducting and non-conducting ratchet teeth on the washer, substantially as described.

3. In an incandescent lamp switch, the combination with the rectangular block 0 of in- Sulating material, having on one side the neck 0 bored to receive a rotatable stem, and in the other side a circular cavity concentric with said bore, and provided with groovesin its end, of an'insulating washer fitting into said cavity and having one or more teeth to engage with said grooves and keep the washer in place substantially as described.

I 4. In an incandescent lamp switch, the combination with a block of insulating material, provided with a cavity, of a washer of hard fiber having ratchet teeth and fittinginto said cavity, said block and Washer having an axial aperture through them, substantially as described.

5. In an incandescent lamp switch, a Washer E of compressed fiberor other insulating material, having one or more teeth e on one face, and four ratchet teeth e on its other face, substantially as described.

6. The combination with, the block C, of the plates F, G and H and the ratchet washer Eall secured to said block, the plates 13 ('1' having fingers f g overlapping two opposite teeth of the ratchet, and a rotatable stem passing through and journaled in said block 0 and carrying a crossbar adapted to slide over said ratchet and connect and disconnect said fingers, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

EDWARD R. KNOWLES.

Witnesses:

MAX LOEWENTHAL, LEWIS T. ROBINSON. 

